Ts. Byun et al., Estimation of fracture toughness transition curves of RPV steels from ballindentation and tensile test data, J NUCL MAT, 277(2-3), 2000, pp. 263-273
It was attempted to estimate the fracture toughness transition curves of re
actor pressure vessel (RPV) steels from the ball indentation and tensile te
st data using the indentation energy to fracture (IEF) model and the relati
onships describing the effect of stress state on fracture. In the IEF model
the fracture toughness is expressed as a function of the ball indentation
test parameters and critical mean contact pressure. From the relationships
among the stress components the fracture stress is derived as a function of
stress triaxiality and flow property. In this approach the fracture stress
calculated for the stress triaxiality of indentation deformation is assume
d as the critical mean contact pressure. Indentation and tensile tests were
performed on six RPV steels at transition temperatures of -160-25 degrees
C. The values of critical mean contact pressure were in the range 2500-2500
MPa, The temperature dependence of the estimated fracture toughness, K-JC
, agreed well with that obtained by the master curve method of ASTM E 1921
using three-point bend (TPB) specimens. In addition, the critical fracture
stresses were obtained by considering the stress triaxiality for the crack
tip. All test materials revealed the values of the critical fracture stress
ranging from 2100 to 2500 MPa. (C) 2000 Elsevier Science B.V. All rights r
eserved.